Mapping hepatitis B virus genotypes on the African continent from 1997 to 2021: a systematic review with meta-analysis.

Hepatitis B virus (HBV) has ten genotypes (A-J) and over 40 sub-genotypes based on the divergence of ≥ 8% and 4 to < 8% in the complete genome respectively. These genotypes and sub-genotypes influence the disease prognosis, response to therapy and route of viral transmission. Besides, infection with mixed genotypes and recombinant genotypes has also been reported. This study aimed at mapping the de novo genotypes and correlate them with the immigration trends in order to inform future research on the underlying reasons for the relative distribution of HBV genotypes from a large sample size pooled from many primary studies. Data was extracted from 59 full research articles obtained from Scopus, PubMed, EMBASE, Willy library, African Journal Online (AJOL) and Google Scholar. Studies that investigated the genotypes, sub-genotypes, mixed genotypes and recombinant were included. The Z-test and regression were used for the analysis. The study protocol is registered with PROSPERO under the registration number CRD42022300220. Overall, genotype E had the highest pooled prevalence significantly higher than all the other genotypes (P < 0.001). By region, genotype A posted the highest pooled prevalence in eastern and southern Africa, E in west Africa and D in north Africa (P < 0.0001). Regarding the emerging genotypes B and C on the African continent, genotype B was significantly higher in south Africa than C (P < 0.001). In contrast, genotype C was significantly higher in east Africa than west Africa (P < 0.0001). The A1 and D/E were the most diverse sub-genotypes and genotype mixtures respectively. Finally, we observed a general progressive decrease in the prevalence of predominant genotypes but a progressive increase in the less dominant by region. Historical and recent continental and intercontinental migrations can provide a plausible explanation for the HBV genotype distribution pattern on the African continent.

Hepatitis B virus (HBV) serological patterns among the HBsAg negative hospital attendees screened for immunization.

The Hepatitis B virus (HBV) is a highly infectious virus and is endemic in Uganda. It is one of the major etiological agents for liver diseases including liver cancer. In this work, we evaluated the prevalence of the HBV serological markers and the associated socio-demographic factors among hepatitis B surface antigen (HBsAg) seronegative persons screened during routine immunization against the virus in eastern Uganda. Data on the socio-demographic characteristics were collected using a structured questionnaire, while that on the serological markers were obtained from serum samples and evaluated by using the 5-panel HBV One Step Hepatitis B Virus Combo Test Device (FastepR, HBV-P43M). The following markers were evaluated by the panel: HBsAg, HBsAb, HBcAb, and HBeAb. Data were analyzed using SPSS (version 26), and multinomial logistic regression was used to elicit the adjusted odds ratio. All the analysis were performed at a 95% confidence limit, and a P value ≤ 0.05 was considered significant. The 424 participants included in this study were mainly female (62.3%), married (55.4%) and aged 30 years and above (54.2%). The seropositivity of the HBsAb, HBeAb, HBcAb marker prevalence rates was 48(11.3%), 73(17.2%) and 45(10.6%) respectively. The majority of the participants (327, 77.1%) did not present with any marker. Married paricipants were significantly associated with reduced HBsAb seropositvity rate, whereas young people aged 18-29 years were associated the with increased odds of HBsAb seropositivity (p < 0.05). Male participants were significantly associated with the HBeAb and HBcAb seropositivity (p < 0.05). Similarly, contact with an HBV infected person was significantly associated with HBeAb and HBcAb seropositivity (p < 0.05). Further still, blood transfusion was significantly associated with the increased risk of HBcAb seropositivity (P < 0.05). This study has revealed a prevalence of HBV serological markers among the HBsAg seronegative persons in this community and an increased risk of transmission of the virus in the community. Our findings have key consequences pertaining the interventions that are pertinent in the control and prevention of the spread of the virus among apparently health persons.

Disproportionate Distribution of HBV Genotypes A and D and the Recombinant Genotype D/E in the High and Low HBV Endemic Regions of Uganda: A Wake-Up Call for Regional Specific HBV Management.

BACKGROUND: Hepatitis B virus (HBV) is the leading cause of liver-related diseases. In Uganda, there is a regional disparity in the HBV burden. Our study was aimed at establishing the circulating genotypes in a low and a high endemic region to give plausible explanations for the differences in regional burden and guide the future management of the disease. METHODS: A total of 200 HBsAg-seropositive subjects were recruited into the study by convenience sampling. The HBsAg Rapid Test Strip (Healgen Scientific Limited Liability Company, Houston, TX77047- USA) was used to screen for HBsAg while the Roche machine (Roche, Basel Switzerland/Abbot Technologies (USA)) was used to determine the viral load. The Chemistry Analyzer B120 (Mindray, China) was used for chemistry analysis. For HBV genotyping, total DNA was extracted from whole blood using the QIAamp® DNA extraction kit. Nested PCR amplification was performed using Platinum Taq DNA Polymerase (Invitrogen Corporation, USA) to amplify the 400 bp HBV polymerase gene. Purification of nested PCR products was performed using Purelink PCR product purification kit (Life Technologies, USA). Automated DNA sequencing was performed using BigDye Terminator v3.1 Cycle Sequencing Kit on 3130 Genetic Analyzer (Applied Biosystems, USA). The NCBI HBV genotyping tool (https://www.ncbi.nlm.nih.gov/projects/genotyping/formpage.cgi) was used for determination of genotype for each HBV sequence. Pearson's chi-square, multinomial logistic regression, and Mann-Whitney U tests were used for the analysis. All the analyses were done using SPSS version 26.0 and MedCalc software version 19.1.3 at 95% CI. A p < 0.05 was considered statistically significant. RESULTS: Majority of our study subjects were female (64.5%), youth (51.0%), and married (62.0%). Overall, genotype A was the most prevalent (46%). Genotype D and the recombinant genotype D/E were proportionately more distributed in the high endemic (38.2%) and low endemic (36.5%) regions, respectively. Genotype D was significantly more prevalent in the high endemic region and among the elderly (p < 0.05). Genotype D was significantly associated with elevated viral load and direct bilirubin (p < 0.05). The recombinant genotype D/E was significantly associated with elevated viral load (p < 0.05). Similarly, genotype A was significantly associated with elevated AST and GGT, lowered viral load, and normal direct bilirubin levels (p < 0.05). CONCLUSION: There is disproportionate distribution of genotypes A and D and the recombinant genotype D/E in the low and high endemic regions of Uganda. This probably could explain the differences in endemicity of HBV in our country signifying the need for regional specific HBV management and control strategies.

Prevalence and predictors of hepatitis B virus (HBV) infection in east Africa: evidence from a systematic review and meta-analysis of epidemiological studies published from 2005 to 2020.

BACKGROUND: The epidemiology of hepatitis B virus (HBV) in the general population in east Africa is not well documented. In this meta-analysis, we examined 37 full published research articles to synthesise up-to-date data on the prevalence and predictors of the HBV burden for the effective prevention and management of the virus in our region. METHODS: We examined 37 full published research articles found using PubMed, Scopus, African Journal Online (AJOL), and Google Scholar between May and October 2020. Dichotomous data on HBV prevalence and predictors of infection were extracted from the individual studies. The HBV prevalence, test of proportion, relative risk, and I2 statistics for heterogeneity were calculated using MedCalc software version 19.1.3. Begg's tests was used to test for publication bias. Sources of heterogeneity were analysed through sensitivity analysis, meta-regression, and sub-group analysis at 95% CI. P < 0.05 was considered significant for all analyses. RESULTS: The prevalence of HBV was generally high (6.025%), with publications from Kenya (8.54%), Uganda (8.454%) and those from between 2011 and 2015 (8.759%) reporting the highest prevalence (P < 0.05). Blood transfusion, scarification, promiscuity, HIV seropositivity, and being male were independent predictors significantly associated with HBV infection (P < 0.05), with the male sex being the most strongly associated predictor of HBV infection. Meta-regressions for the pooled HBV prevalence and sample size, as well as the year of publication, lacked statistical significance (P > 0.05). Omitting the study with the largest sample size slightly increased pooled HBV prevalence to 6.149%, suggesting that the studies are robust. Begg's test showed no evidence of publication bias for overall meta-analysis (p > 0.05). CONCLUSION: The burden of HBV is still high, with the male sex, blood transfusion, body scarification, and HIV seropositivity being potential predictors of infection. Thus, it is important to scale up control and prevention measures targeting persons at high risk.

Sero-prevalence of human immunodeficiency virus-hepatitis B virus (HIV-HBV) co-infection among pregnant women attending antenatal care (ANC) in sub-Saharan Africa (SSA) and the associated risk factors: a systematic review and meta-analysis.

BACKGROUND: There is plenitude of information on HIV infection among pregnant mothers attending antenatal care (ANC) in sub-Saharan Africa. However, the epidemiology of HBV-HIV co-infections in the same cohort is not clear despite the common route of transmission of both viruses. The aim of our study was to synthesize data on the prevalence of HBV-HIV co-infection among pregnant women attending ANC in Sub-Saharan Africa to assist in the design of public health interventions to mitigate the challenge. METHODS: The study was done in tandem with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) standards and the Cochran's Q test, I2 statistics for heterogeneity and the prevalence were calculated using commercially available software called MedCalcs ( https://www.medcalc.org ). A random effect model was used to pool the prevalence since all the heterogeneities were high (≥ 78%) and Phet < 0.05 indicated significant heterogeneities. The risk factors and risk differences for HBV-HIV co-infection were analyzed. Any likely sources of heterogeneity were analyzed through sensitivity analysis, meta-regression and sub-group analysis. All analyses were done at 95% level of significance and a P < 0.05 was considered significant. RESULTS: The overall pooled prevalence of HBV-HIV co-infection among pregnant mothers in sub-Saharan Africa was low 3.302% (95%CI = 2.285 to 4.4498%) with heterogeneities (I2) of 97.59% (P > 0.0001). Within regional sub group meta-analyses, West Africa had significantly higher prevalence of 5.155% (95% = 2.671 to 8.392%) with heterogeneity (I2) of 92.25% (P < 0.0001) than any other region (P < 0.001). Articles published from 2004-2010 had significantly higher prevalence of 6.356% (95% = 3.611 to 9.811%) with heterogeneity (I2) 91.15% (P < 0.0001) compared to those published from 2011 to 2019 (P < 0.001). The HIV positive cohort had significantly higher prevalence of HBV-HIV co-infection of 8.312% (95% CI = 5.806 to 11.22%) with heterogeneity (I2)94.90% (P < 0.0001) than the mothers sampled from the general population with a prevalence of 2.152% (95% CI = 1.358 to 3.125%) (P < 0.001). The overall and sub group analyses had high heterogeneities (I2 > 89%, P < 0.0001) but was reduced for South Africa (I2) = 78.4% (P = 0.0314). Age, marital status and employment were independent factors significantly associated with risk of HBV-HIV co-infection (P < 0.001) but not extent of gravidity and education level (P > 0.05). After meta-regression for year of publication and sample size for HBsAg positivity, the results were not significantly associated with HBV pooled prevalence for sample size (P = 0.146) and year of publication (P = 0.560). Following sensitivity analysis, the HBsAg pooled prevalence slightly increased to 3.429% (95% CI = 2.459 to 4.554%) with heterogeneity I2 = 96.59% (95% CI = 95.93 to 97.14%), P < 0.0001 CONCLUSION: There is an urgent need for routine HBV screening among HIV positive pregnant mothers attending antenatal care in sub-Saharan Africa to establish the extent of HBV-HIV co-infection in this cohort. Future studies need to investigate the putative risk factors for HBV-HIV co-infection and prioritize plausible control strategies.

Multiple sclerosis risk variant HLA-DRB1*1501 associates with high expression of DRB1 gene in different human populations.

The human leukocyte antigen (HLA) DRB1*1501 has been consistently associated with multiple sclerosis (MS) in nearly all populations tested. This points to a specific antigen presentation as the pathogenic mechanism though this does not fully explain the disease association. The identification of expression quantitative trait loci (eQTL) for genes in the HLA locus poses the question of the role of gene expression in MS susceptibility. We analyzed the eQTLs in the HLA region with respect to MS-associated HLA-variants obtained from genome-wide association studies (GWAS). We found that the Tag of DRB1*1501, rs3135388 A allele, correlated with high expression of DRB1, DRB5 and DQB1 genes in a Caucasian population. In quantitative terms, the MS-risk AA genotype carriers of rs3135388 were associated with 15.7-, 5.2- and 8.3-fold higher expression of DQB1, DRB5 and DRB1, respectively, than the non-risk GG carriers. The haplotype analysis of expression-associated variants in a Spanish MS cohort revealed that high expression of DRB1 and DQB1 alone did not contribute to the disease. However, in Caucasian, Asian and African American populations, the DRB1*1501 allele was always highly expressed. In other immune related diseases such as type 1 diabetes, inflammatory bowel disease, ulcerative colitis, asthma and IgA deficiency, the best GWAS-associated HLA SNPs were also eQTLs for different HLA Class II genes. Our data suggest that the DR/DQ expression levels, together with specific structural properties of alleles, seem to be the causal effect in MS and in other immunopathologies rather than specific antigen presentation alone.

High ACSL5 transcript levels associate with systemic lupus erythematosus and apoptosis in Jurkat T lymphocytes and peripheral blood cells.

BACKGROUND: Systemic lupus erythematosus (SLE) is a prototypical autoimmune disease in which increased apoptosis and decreased apoptotic cells removal has been described as most relevant in the pathogenesis. Long-chain acyl-coenzyme A synthetases (ACSLs) have been involved in the immunological dysfunction of mouse models of lupus-like autoimmunity and apoptosis in different in vitro cell systems. The aim of this work was to assess among the ACSL isoforms the involvement of ACSL2, ACSL4 and ACSL5 in SLE pathogenesis. FINDINGS: With this end, we determined the ACSL2, ACSL4 and ACSL5 transcript levels in peripheral blood mononuclear cells (PBMCs) of 45 SLE patients and 49 healthy controls by quantitative real time-PCR (q-PCR). We found that patients with SLE had higher ACSL5 transcript levels than healthy controls [median (range), healthy controls = 16.5 (12.3-18.0) vs. SLE = 26.5 (17.8-41.7), P = 3.9×10 E-5] but no differences were found for ACSL2 and ACSL4. In in vitro experiments, ACSL5 mRNA expression was greatly increased when inducing apoptosis in Jurkat T cells and PBMCs by Phorbol-Myristate-Acetate plus Ionomycin (PMA+Io). On the other hand, short interference RNA (siRNA)-mediated silencing of ACSL5 decreased induced apoptosis in Jurkat T cells up to the control levels as well as decreased mRNA expression of FAS, FASLG and TNF. CONCLUSIONS: These findings indicate that ACSL5 may play a role in the apoptosis that takes place in SLE. Our results point to ACSL5 as a potential novel functional marker of pathogenesis and a possible therapeutic target in SLE.

Tag-SNP analysis of the GFI1-EVI5-RPL5-FAM69 risk locus for multiple sclerosis.

A recent genome-wide association study conducted by the International Multiple Sclerosis Genetic Consortium (IMSGC) identified, among others, a number of putative multiple sclerosis (MS) susceptibility variants at position 1p22. Twenty-one SNPs positively associated with MS were located at the GFI-EVI5-RPL5-FAM69A locus. In this study, we performed an analysis and fine mapping of this locus, genotyping eight Tag-SNPs in 732 MS patients and 974 controls from Spain. We observed an association with MS in three of eight Tag-SNPs: rs11804321 (P=0.008, OR=1.29; 95% CI=1.08-1.54), rs11808092 (P=0.048, OR=1.19; 95% CI=1.03-1.39) and rs6680578 (P=0.0082, OR=1.23; 95% CI=1.07-1.41). After correcting for multiple comparisons and using logistic regression analysis to test the addition of each SNP to the most associated SNPs, we observed that rs11804321 alone was sufficient to model the association. This Tag-SNP captures two SNPs in complete linkage disequilibrium (r(2)=1), both located within the 17th intron of the EVI5 gene. Our findings agree with the corresponding data of the recent IMSGC study and present new genetic evidence that points to EVI5 as a factor of susceptibility to MS.

Hexose-6-phosphate dehydrogenase: a new risk gene for multiple sclerosis.

A recent genome-wide association study (GWAS) performed by the The Wellcome Trust Case-Control Consortium based on 12 374 nonsynonymous single-nucleotide polymorphisms (SNPs) provided evidence for several genes involved in multiple sclerosis (MS) susceptibility. In this study, we aimed at verifying the association of 19 SNPs with MS, with P-values < or =0.005, in an independent cohort of 732 patients and 974 controls, all Caucasian from the South of Spain. We observed an association of the rs17368528 polymorphism with MS (P=0.04, odds ratio (OR)=0.801, 95% confidence interval (CI)=0.648-0.990). The association of this polymorphism with MS was further validated in an independent set of 1318 patients from the Canadian Collaborative Project (P=0.04, OR=0.838, 95% CI=0.716-0.964). This marker is located on chromosome 1p36.22, which is 1 Mb away from the MS-associated kinesin motor protein KIF1B, although linkage disequilibrium was not observed between these two markers. The rs17368528 SNP results in an amino-acid substitution (proline to leucine) in the fifth exon of the hexose-6-phosphate dehydrogenase (H6PD) gene, in which some variants have been reported to attenuate or abolish H6PD activity, in individuals with cortisone reductase deficiency. This study corroborates the association of one locus determined by GWAS and points to H6PD as a new candidate gene for MS.

IL2RA/CD25 gene polymorphisms: uneven association with multiple sclerosis (MS) and type 1 diabetes (T1D).

BACKGROUND: IL-2 receptor (IL2R) alpha is the specific component of the high affinity IL2R system involved in the immune response and in the control of autoimmunity. METHODS AND RESULTS: Here we perform a replication and fine mapping of the IL2RA gene region analyzing 3 SNPs previously associated with multiple sclerosis (MS) and 5 SNPs associated with type 1 diabetes (T1D) in a collection of 798 MS patients and 927 matched Caucasian controls from the south of Spain. We observed association with MS in 6 of 8 SNPs. The rs1570538, at the 3'- UTR extreme of the gene, previously reported to have a weak association with MS, is replicated here (P = 0.032). The most associated T1D SNP (rs41295061) was not associated with MS in the present study. However, the rs35285258, belonging to another independent group of SNPs associated with T1D, showed the maximal association in this study but different risk allele. We replicated the association of only one (rs2104286) of the two IL2RA SNPs identified in the recently performed genome-wide association study of MS. CONCLUSIONS: These findings confirm and extend the association of this gene with MS and reveal a genetic heterogeneity of the associated polymorphisms and risk alleles between MS and T1D suggesting different immunopathological roles of IL2RA in these two diseases.

Rapid increase in resistance of Plasmodium falciparum to chloroquine-Fansidar in Uganda and the potential of amodiaquine-Fansidar as a better alternative.

Combinations of chloroquine (CQ) and sulfadoxine-pyrimethamine (SP) [CQSP] as the first line agents in Uganda have replaced CQ monotherapy. The idea of the combination is to delay the development of malaria resistance to either drug when used alone. We compared the clinical, parasitological and molecular findings of two studies with treatment arms of CQSP, amodiaquine (AQ) plus SP (AQSP) both done in 2003 with a study done 1 year earlier (2002) using SP alone. There was a notable decrease in adequate clinical response (ACR) by day 14 from 92.7% with SP to 80% with the combination CQSP, a year later. AQSP combination was found to have the best effect (94.3% ACR). There were no early treatment failures in the AQSP group. However, treatment failures were recorded at 20% on day 14 and 43% on day 28 for CQSP treatment and 5.7% by day 14 and 28.8% by day 28 in the AQSP group. The number of mutations that are associated with SP resistance increased from 2002 to 2003 at all loci monitored, from 83.8 to 100% at codon 108, 58.7 to 76% at codon 59 in the DHFR gene, and from 58.8 to 86% at codon 437 and 33 to 43% at codon 540 in the DHPS gene. We conclude that there has been a rapid development of resistance since the introduction of the new policy guidelines. AQSP was found to be a superior drug combination compared to CQSP and could be used as a low cost alternative at the moment.